source: trunk/third/nmh/sbr/seq_list.c @ 12455

/*
 * seq_list.c -- Get all messages in a sequence and return them
 *            -- as a space separated list of message ranges.
 *
 * $Id: seq_list.c,v 1.1.1.1 1999-02-07 18:14:10 danw Exp $
 */

#include <h/mh.h>

/* allocate this much buffer space at a time */
#define MAXBUFFER 1024

/* static buffer to collect the sequence line */
static char *buffer = NULL;
static int len = 0;


char *
seq_list(struct msgs *mp, char *seqname)
{
    int i, j, seqnum;
    char *bp;

    /* On first invocation, allocate initial buffer space */
    if (!buffer) {
        len = MAXBUFFER;
        if (!(buffer = malloc ((size_t) len)))
            adios (NULL, "unable to malloc storage in seq_list");
    }

    /*
     * Special processing for "cur" sequence.  We assume that the
     * "cur" sequence and mp->curmsg are in sync (see seq_add.c).
     * This is returned, even if message doesn't exist or the
     * folder is empty.
     */
    if (!strcmp (current, seqname)) {
        if (mp->curmsg) {       
            sprintf(buffer, "%s", m_name(mp->curmsg));
            return (buffer);
        } else
            return (NULL);
    }

    /* If the folder is empty, just return NULL */
    if (mp->nummsg == 0)
        return NULL;

    /* Get the index of the sequence */
    if ((seqnum = seq_getnum (mp, seqname)) == -1)
        return NULL;

    bp = buffer;

    for (i = mp->lowmsg; i <= mp->hghmsg; ++i) {
        /*
         * If message doesn't exist, or isn't in
         * the sequence, then continue.
         */
        if (!does_exist(mp, i) || !in_sequence(mp, seqnum, i))
            continue;

        /*
         * See if we need to enlarge buffer.  Since we don't know
         * exactly how many character this particular message range
         * will need, we enlarge the buffer if we are within
         * 50 characters of the end.
         */
        if (bp - buffer > len - 50) {
            char *newbuf;

            len += MAXBUFFER;
            if (!(newbuf = realloc (buffer, (size_t) len)))
                adios (NULL, "unable to realloc storage in seq_list");
            bp = newbuf + (bp - buffer);
            buffer = newbuf;
        }

        /*
         * If this is not the first message range in
         * the list, first add a space.
         */
        if (bp > buffer)
            *bp++ = ' ';

        sprintf(bp, "%s", m_name(i));
        bp += strlen(bp);
        j = i;                  /* Remember beginning of message range */

        /*
         * Scan to the end of this message range
         */
        for (++i; i <= mp->hghmsg && does_exist(mp, i) && in_sequence(mp, seqnum, i);
             ++i)
            ;

        if (i - j > 1) {
            sprintf(bp, "-%s", m_name(i - 1));
            bp += strlen(bp);
        }
    }
    return (bp > buffer? buffer : NULL);
}